Process and composition for well dispersed, highly loaded color masterbatch

ABSTRACT

A highly loaded and well-dispersed masterbatch composition and process for making thereof from a split stream process. The masterbatch composition includes a colorant, a thermoplastic carrier, a metallocene polymer processing aid, and optionally an additive. The split stream may be formed of a primary feed and a secondary feed. The primary and second feeds are combined by at least one of the following: supplying the secondary feed in either the same feed port as the primary feed, in a stream located upstream the primary feed, in a stream located downstream the primary feed, or a combination thereof.

RELATED APPLICATIONS

This application claims priority to U.S. patent application Ser. No.14/334,710 filed on Jul. 18, 2014, which is incorporated by reference inits entirety herein.

TECHNICAL FIELD

The present disclosure relates in general to a process and compositionfor well dispersed, highly loaded color masterbatch formulations from asplit stream extrusion process, optionally including one or moreadditives. The highly loaded color masterbatch may contain one colorantor a formulated blend of colorants.

BACKGROUND

Colorants such as pigment preparations are often produced formasterbatches. A masterbatch is an encapsulated, pelletized, orgranular, dust-free concentrate of a plastomeric or elastomeric polymercomprising a fraction of a colorant. Masterbatches are used to colorplastics, being added to the plastic to be colored prior to or duringprocessing. Masterbatches are used because they provide better colorantdispersion than neat colorant and eliminate dry colorant dust from theworkplace.

A variety of processes for producing masterbatches are known and thefollowing processes are standard in the production of the masterbatches:a) the mixing of a suitable matrix (polymers) with the colorant; b) dryblending/extrusion and kneading with subsequent grinding of the colorantconcentrate; or c) dry blending/extrusion and subsequent fine spraying,hot chopping, or strand pelletizing. For example, as described in U.S.Pat. No. 7,442,742, a masterbatch composition is formed from dryblending/extrusion of a colorant, a thermoplastic carrier, a metallocenepolymer processing aid, and optionally an additive. In comparison toU.S. Pat. No. 7,442,742, the present invention enables up to 20% orhigher loadings of active ingredients.

Split stream feeding can be utilized in extrusion processing ofplastics, food products, printing toners, latex, and other materials.Split stream feeding describes the use of two or more feed streamsdirected to processing in an extruder.

In the production of thermoplastic laminate structures, such as in U.S.Pat. No. 4,165,210, Corbett, August 1979, plastic laminated sheetstructures are produced by the combination of two streams of moltenplastic and that create a laminar flow through a die yielding a laminarsheet or tube. In U.S. Pat. No. 4,909,726, Bekele, March 1990, acoextrusion process is described in which polymer streams from multipleextruders are combined at the die of one of the extruders to form amultilayer film. In U.S. Pat. No. 5,660,922, Herridge et al., August1997, a coextrusion process for making tapes is described in detail.

With regard to downstream feeding of temperature sensitive components inplastics and food processing, in U.S. Pat. No. 4,409,165, Kim, October1983, describes how a temperature sensitive blowing agent is introducedas a separate feed downstream of the polymer feed at a point where thepolymer is compacted but not yet molten, thereby reducing thetemperature at which fusion takes place. In U.S. Pat. No. 6,649,666,Read et al., November 2003, another process is described in which a feedstream of a blowing agent is introduced separately from the polymer feedstream. In the extrusion processing of foods, water is often added as aseparate feed stream, typically downstream to control evaporativelosses, such as described in U.S. Pat. No. 4,759,939, Keller et al.,July 1988, U.S. Pat. No. 4,880,653, Keller et al., and U.S. Pat. No.4,949,628 van Lengerich, August 1990. In U.S. Pat. No. 4,965,082, Chawanet al., October 1990, describes downstream feeding of liquid ingredientsin pasta production.

In the art of downstream feeding of mechanically fragile materials, suchas special effects pigments and functional fillers with high aspectratio, U.S. Pat. No. 4,495,324, Chako et al., January 1985, describesfeeding short glass fibers into an extruder downstream of the polymerpellet feed into the molten polymer to make a glass fiber reinforcedcomposite. Additional examples of downstream feeding of mechanicallyfragile materials include U.S. Pat. No. 5,621,040, April 1997, and U.S.Pat. No. 5,723,520, March 1998, Akapeddi et al. U.S. Pat. No. 6,776,596,Brussel, August 2004, which describe feeding long glass fibersdownstream into the polymer stream, post melting, to create a highstrength glass reinforced composite. As described in U.S. Pat. No.7,488,764, Hobbs et al., February 2009, high aspect ratios areencapsulated in microspheres which are subsequently fed at the primaryfeed port along with polymer pellets and also downstream of the pelletsinto the melt. U.S. Patent Application 2011/0073799, Magni et al., March2011, describes composites produced by downstream feeding up to 35% highaspect ratio particles that enhance thermal conductivity of the polymer.

The downstream feeding of lubricants is described in U.S. Pat. No.4,446,090, Lovgren et al., May 1984, U.S. Pat. No. 4,877,568, Austin,May 1988, and U.S. Pat. No. 5,531,923, Le Blanc et al., July 1996, whichdetail feeding liquid lubricants downstream of the polymer feed into themolten polymer. In U.S. Pat. No. 5,486,327, Bemis et al., describes asimilar process in which liquid color concentrates, which often containoils, are introduced downstream of the polymer to extrude a coloredplastic.

Whereas, downstream feeding of liquid components to adjust the viscosityof a material is described in U.S. Pat. No. 5,316,578, Buehler et al.,May 1994, and U.S. Pat. No. 5,480,923, Schmid et al., January 1996, withregard to extrusion processing of starch products and the introductionof liquids downstream to reduce product viscosity in a controlledfashion.

The downstream feeding of particulate additives and fillers is describedin patent literature with regard to particulate functional additives andfillers in the production of plastics materials. U.S. Pat. No.4,906,421, Plamthottam, January 1990, describes downstream feeding offillers, U.S. Pat. No. 5,969,089, October 1999, describes adding fillersand functional additives downstream of resins, and U.S. Pat. No.6,242,127, June 2001, describes downstream addition of functionaladditives in a film extrusion process.

Downstream feeding of flame retardant additives is described in U.S.Pat. No. 6,713,598, Selvaraj et al., March 2004, U.S. Pat. No.6,800,677, Yakobe, October 2004, which also includes downstream feedingof glass fibers for reinforcement, and U.S. Pat. No. 7,939,585, Gaggaret al., May 2011.

U.S. Pat. No. 6,287,692, Luo et al., September 2001, describes extrusionprocessing of wire and cable compounds in which particulate additivesare introduced downstream of the polymer feed.

U.S. Pat. No. 8,367,755 describes polyphenylene ether thermoplasticcompounds for sheet extrusion and molding in which additives areintroduced downstream of the polymer feed during extrusion processing tomake the compounds.

The use of split resin streams in the production of polymer alloys andblends via extrusion processing is described in U.S. Pat. No. 4,547,541,Golba, October 1985; U.S. Pat. No. 5,225,488, Baird et al., July 1993,U.S. Pat. No. 5,420,198, Papazoglou et al., May 1995; U.S. Pat. No.7,182,886, Elkovitch et al., February 2007; U.S. Pat. No. 7,868,090,Ellul et al., January 2011; U.S. Pat. No. 8,148,466, Wood et al., April,2012.

Split stream feeding in reactive extrusion processes is known anddescribed in U.S. Pat. No. 7,148,314, Gallucci et al., December 2006,which details feeding of a component with a desired functional groupdownstream of a polymer to then react with it and yield a functionalizedpolymer, and U.S. Pat. No. 7,829,640, Barbieri et al., November 2010,which details an extrusion reaction process in which the output streamis fed back to the feed throat for further reaction.

Adding a colorant feed downstream of the resin feed is described in U.S.Pat. No. 6,352,654, Silvy et al., March 2002, and U.S. Pat. No.6,776,929, Hossen, August 2004, with regard to the production of anelectrically conductive polymer via extrusion processing in whichconductive carbon black powder or masterbatch is introduced downstreamof the polymer feed into the melt.

Utilization extrusion processing in which a molten polymer is fed as asecond feed stream has been described in U.S. Pat. No. 5,376,702, Stibelet al., December 1994, wherein a process in which a secondary polymerstream is split off, combined with other components, and then recombinedwith the primary polymer stream. In U.S. Pat. No. 6,010,723, Song etal., January 2000, a process is described for making chewing gum inwhich components of the recipe are compounded in a first extruder whichthen feeds its output to a second extruder into which are also fedcomponents that will reduce the viscosity of the melt stream fromextruder 1.

Extrusion compounding of a complex mixture of particulates, liquids, andresins in which a binder is fed downstream has been discussed in U.S.Pat. No. 4,894,308, Mahabadi et al., January 1990, wherein extrusionprocessing occurs of electrostatic dry printing toners by utilizing adry blend of surfactants and pigments at the main feed port, which aremelted under heat and pressure, and then conveyed past a second feedport where a polymer is introduced as a powder or pellets. In U.S. Pat.No. 7,572,567, Chung et al., August 2009, describes a process in whichan aqueous solution of poly Aluminum Chloride is introduced downstreamas a coagulating binder into the melt stream of pigments and othercomponents of an electrostatic toner for dry printing.

The described art is related to materials that were intended to befabricated into parts or materials and methods for fabricatingconstructions. In contrast, the present invention relates to a processand materials for making an intermediate that is used to colorthermoplastic materials; specifically, color and additive masterbatches.

In Stibel et al. (U.S. Pat. No. 5,376,702, December 1994), a separatemolten polymer stream is combined with additives, and then recombinedwith a primary feed. In contrast, the present invention describes thecounter-intuitive process of premelting the majority of the resincomponent of a masterbatch formulation which serves as the carrier orbinder to increase the density to (i) create additional free volume inthe feed throat for adding colorants and additives and (ii) start thepigment wetting process immediately upon contact with the resin.

Song et al. (U.S. Pat. No. 6,010,723, January 2000 and earlier patents)describes feeding the output of an extruder into the primary feed of asecond extruder for the purpose of introducing viscosity reducingadditives via the second extruder. Whereas, in present invention, themajority of the resin component of a masterbatch formulation ispre-melted, and serves as the carrier or binder to densify theformulation to (i) create additional free volume in the feed throat foradding colorants and additives and (ii) begin the pigment wettingprocess immediately upon contact with the resin.

The invention also differs from Corbett, U.S. Pat. No. 4,165,210, August1979 which describes the concept of bringing streams of molten plastictogether in a die to form laminate structures. Similar difference existbetween the current invention and the coextrusion processes described byBekele, U.S. Pat. No. 4,909,726, March 1990, and Herridge et al., U.S.Pat. No. 5,660,922, August 1997.

The concept of adding pigments downstream of a resin feed is known, forexample, U.S. Pat. No. 6,352,654, Silvy et al., March 2002, and U.S.Pat. No. 6,776,929, Hossen, August 2004 describe production of anelectrically conductive polymer via extrusion processing in whichconductive carbon black powder or masterbatch is introduced downstreamof the polymer feed into the melt, where the carbon black is a minorcomponent of the total composition. However, the invention relates tothe downstream addition of pigments comprising up to 80% of the totalcomposition.

Various patents describe downstream feeding of fillers, such as shortglass fibers and composites with up to 70% glass fiber, which arecommercially available. Colorants, however, have a much higher surfacearea to wet out, and as noted above, are dosed in as minor componentsdownstream.

The prior art fails to describe introducing a pre-melted resin carrierfeed downstream of the powder feed. Nor is the concept of pre-meltingthe resin feed for the combined purposes of increasing the volumeavailable for the powders to achieve higher loading than previouslypossible and initiating the wetting out process on contact. Theinvention described herein provides a volume enhancement in the primaryfeed in which the polymer melt feed and the colorant mix feed areintroduced at the same primary feed throat. Furthermore, none of thepatents described relate to the introduction of the polymer feed as amolten stream that is the output of a second melt processing unit, orfeeding the resin stream is upstream of the colorant mix feed. Themethods cited in the prior art describe an extrusion process in whichthe resin is compressed and melted in the extruder prior to reaching thezone where the downstream feed port is located. However, as described indetail herein, there are advantages in pre-melting the resin in aseparate device: (i) the compression, kneading, and melting zones of theprimary extruder can be minimized; (ii) the process is more energyefficient in that more of the energy supplied to the extruder is used toaffect incorporation and dispersion of the colorants and additives,enabling higher production rates, and (iii) a simple single screwextruder or melt pump can be used to pre-melt the polymer. Based onthis, the total cost of the combined system can be lower or comparablethan that of the conventional extruder alone.

Known masterbatches formed from dry blending/extrusion are generallyformulated using a method which includes a thermoplastic polymer, acolorant, a dispersant, and optionally one or more additives. Thethermoplastic polymer is commonly referred to as a “carrier” or “carrierresin.” A typical commercial formulation of a masterbatch, particularlyformulated with a mixture of colorants (pigments and dyes) includesabout 30% by weight of colorant, about 5% by weight of dispersant, about10% by weight of additive, and about 55% by weight of a carrier.

Unfortunately, known masterbatches formed from dry blending/extrusion,particularly those comprised of blends of colorants (pigments and dyes)have a relatively low colorant concentration. Thus, it has been foundthat many known masterbatches introduce unnecessary costs and undesiredamounts of auxiliary ingredients, such as carrier matrix. Particularlyin the case of colorant formulations containing relatively highproportions of organic pigments, higher loadings of colorant cannot beused in known masterbatches produced from dry pigments due toinsufficient dispersion. Insufficient dispersion of the colorantparticles can lead to a decrease in physical and mechanical propertiesof the end product, such as tensile strength, flexural modulus,elongation, and impact strength. Also, pigment agglomerates can lead tosurface imperfections that affect the part's appearance.

Organic pigment dispersion in conventionally produced masterbatches canbe improved by using mostly or entirely powdered or finely granulatedresins. However, this practice results in introducing dry blend mixturesof resin, colorants, and other ingredients having a significantly lowerbulk density than mixtures with resin pellets. Less material isintroduced into the extruder in any given time, resulting in asignificant reduction in processing rate.

Another deficiency in known dry blending/extrusion masterbatchcompositions is the inability to significantly improve theprocessability of the masterbatch itself and the end product.

Another deficiency in known dry blending/extrusion masterbatchprocessing is the blend volume limitation in the feed throat of anextruder. Fixed volume in the feed throat limits pigment and additiveloadings, particularly in the case of organic pigments and certaineffects pigments, such as pearlescent pigments, due to the low bulkdensity of these pigments. Similarly, these limitations on the amount ofmaterial introduced at the feed throat significantly reduce extrusionthroughput and color strength.

Problems due to the fixed volume in the feed throat could be alleviatedby increasing the free volume in the feed throat by using thinnerflights, adding deeper roots on the screw, and extending the length ofthe opening; however, all of these attempts will only provide smallincremental gains in the volume space (e.g. 10-15% more free volumespace), do not provide the desired increase in pigment and additiveloading, and sacrifice the strength and life of the screw.

Another deficiency in known dry blending/extrusion masterbatchcompositions is the inability to include relatively significant amountsof loading with regard to additives such as ultraviolet light absorbers,light stabilizers, antioxidants, and blowing agents. Generally,additives are added only if desired and then in small amounts.Otherwise, it is believed that the processability of the masterbatchwould be impaired.

In addition, other deficiencies in processing known dryblending/extrusion masterbatch compositions are inefficiencies of thework provided by the extruder and inefficiencies of the length of theextrusion cycle. Specifically, much of the energy and residence time isspent melting the polymer carrier instead of dispersing colorants.

Presently, there is no known system or method for providing amasterbatch composition that avoids the foregoing problems associatedwith conventional masterbatches. Accordingly, it is desirable to providea masterbatch composition with improved processability that increasesloading of the masterbatch composition as well as the coloration of theend product without sacrificing production rate, production throughput,physical and mechanical properties of the colored parts, and surfaceappearance, all the while introducing less carrier resin into the endpart.

The present application, as described and claimed herein, addresses theabove described deficiencies of prior art masterbatches and processesfor developing the same.

SUMMARY

In one aspect, the present disclosure is directed to a process formaking a masterbatch that includes mixing a colorant, an additive, athermoplastic carrier, and optionally a metallocene polymer processingaid, and then adding a majority of the carrier resin in a molten stateeither to a port located at the primary feed, upstream the primary feed,downstream of the primary feed, or a combination thereof. While it isnot uncommon to introduce additives and colorants as a separate streamin melt processing thermoplastics, generally downstream of the mainfeed, it is counterintuitive in conventional masterbatch processing tointroduce the majority of the resin to a primary extruder as a meltstream generated by a secondary extruder or melt pump.

The present disclosure is directed to a masterbatch composition producedby using a split stream feed, which includes a main or primary feedhaving a colorant, a polymer processing aid, and optionally an additiveand carrier resin, and a secondary feed including a majority of thecarrier resin in a molten state either connected to the same feed as theprimary feed, upstream the primary feed, downstream of the primary feed,or a combination thereof. The primary feed is largely composed ofcolorants, pigments, powdered resins, processing aids, and functionaladditives such as UV, AO, slip, antistats, anti-microbial, FR, etc. Theprimary feed may be a powder feed, a colorant mix feed, and/or a smallgranule feed.

In a further aspect, the present disclosure is directed to a process formaking a colorized polymer that includes introducing a highly-loadedmasterbatch composition to a melt-processible polymer to form a meltfeed polymer composition, wherein the masterbatch comprises a colorant,a thermoplastic carrier, a metallocene polymer processing aid, andoptionally an additive, and extruding the polymer composition to formthe colorized polymer.

In an embodiment, a process for making a highly loaded andwell-dispersed masterbatch composition from a split stream processcomprises the following steps: a) mixing a colorant in a mixture in aprimary feed; b) pre-melting a thermoplastic carrier in a secondaryfeed; and c) combining the mixture of the primary feed and the meltedthermoplastic carrier of the secondary feed to form the masterbatchcomposition. Using the masterbatch composition from this process, athermoplastic article may be produced.

In an embodiment, the mixing step includes an additive in the primaryfeed, the secondary feed, or a combination thereof.

In an embodiment, the mixing step includes a metallocene polymerprocessing aid in a primary feed, wherein the metallocene polymerprocessing aid is a polyolefin. The metallocene polymer processing aidmay be an amorphous metallocene polypropylene copolymer obtained bypolymerizing a propylene monomer with about 2-15% ethylene comonomer inthe presence of a metallocene catalyst. Further, the metallocene polymerprocessing aid may exhibit a density of about 0.87-0.93 g/cm3, a droppoint of about 80-145° C., and a viscosity of about 60-6300 mPas.

The combining step may further include supplying the secondary feed to aport located by the primary feed, upstream the primary feed, downstreamthe primary feed, or a combination thereof. The combining step mayfurther include supplying an additive in the primary feed, the secondaryfeed, or a combination thereof.

An additive may be selected from the group consisting of antioxidants,ultraviolet light absorbers, light stabilizers, flame-retardants,antibacterial agents, surface tension reducers, deodorizing agents,anti-static agents, anti-blocking agents, plasticizer agents, fillers,and blowing agents.

The additive may further include an antioxidant of about 0-15% byweight, a light stabilizer about 0-45% by weight, and an ultravioletlight absorber about 0-45% by weight. In an embodiment, the additive isabout 5-60% by weight.

The colorant may be about 15-80% by weight, the thermoplastic carrier isabout 9-60% by weight, and the metallocene polymer is about 2-20% byweight. The colorant may be selected from the group consisting oforganic pigment, inorganic pigment, single pigment dispersion, dye,coated mica, powdered aluminum, optical brightener, fluorescent, andphosphorescent. The colorant may include an organic pigment about 5-50%by weight. The colorant may include an organic pigment about 10-40% byweight. The colorant may include an inorganic pigment about 0-80% byweight. Further, the colorant may include an organic pigment about 3-40%by weight and an inorganic pigment about 10-60% by weight.

The thermoplastic carrier may be selected from at least one of thefollowing: homopolymers and copolymers of polyethylene, polypropylene,polystyrene, polyoxymethylene, polyethylene terephthalate, polybutyleneterephthalate, polymethyl methacrylate, polyether sulfones,polysulfones, polyether ketones, polystyrene copolymers,acrylonitrile-butadiene-styrene terpolymers, polyamides, polycarbonate,and combinations thereof.

The process may further include a dispersion package. In an embodiment,a dispersion package is selected from the group consisting of waxes,metal salts, coupling agents, and surfactants. The dispersion packagemay be about 2-8% by weight. The process may further include one of thefollowing: flame-retardants, antibacterial agents, surface tensionreducers, deodorizing agents, anti-static agents, anti-blocking agents,plasticizer agents, fillers, and blowing agents.

A process for making a highly loaded and well-dispersed masterbatchcomposition may further include the steps of: a) introducing amasterbatch composition formed from a split stream process, as providedin claim 1, to a melt-processible polymer to form a feed polymercomposition, wherein the masterbatch composition comprises a pigment, athermoplastic carrier, and, greater than 5% to about 60% by weight of anadditive, wherein the additive is selected from the group consisting ofantioxidants, ultraviolet light absorbers, and light stabilizers; and b)processing the polymer composition to form the masterbatch composition.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood by reference to thefollowing detailed description taken in connection with the followingillustrations, wherein:

FIG. 1 is a process flow diagram for making a highly loaded andwell-dispersed masterbatch composition from a split stream process in anembodiment;

FIG. 2 is a process flow diagram for making a highly loaded andwell-dispersed masterbatch composition from a split stream process inanother embodiment; and

FIG. 3 is a process flow diagram for making a highly loaded andwell-dispersed masterbatch composition from a split stream process inyet another embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments of thepresent teachings, examples of which are illustrated in the accompanyingdrawings. It is to be understood that other embodiments may be utilizedand structural and functional changes may be made without departing fromthe respective scope of the present teachings. Moreover, features of thevarious embodiments may be combined or altered without departing fromthe scope of the present teachings. As such, the following descriptionis presented by way of illustration only and should not limit in any waythe various alternatives and modifications that may be made to theillustrated embodiments and still be within the spirit and scope of thepresent teachings.

A masterbatch composition having a colorant and optionally one or moreadditives is provided. This disclosure describes the use of split streamfeed processing equipment to make relatively highly loaded colorconcentrates and additives. The masterbatch composition of the presentdisclosure exhibits excellent colorant dispersability, coloringproperties, increased additive concentrations, as well as improvedhandleability, so that the colored end product has excellent physicaland mechanical strength as well as excellent coloration. The presentmasterbatch composition optionally includes a metallocene polymerprocessing aid that substantially eliminates many of the practicalproblems and limitations encountered in the current art. The optionalmetallocene polymer processing aid is compatible with various carrierresins, allows for decreasing the amount of conventional carrier resin,and also provides better mechanical and physical properties of the endproducts. The masterbatch split stream process allows for extraordinaryincreases in colorant loading compared to known processes. As theconcentration of colorants and additives is increased, the amount of themasterbatch composition required to achieve the desired end productproperties can be appreciably lower than conventional masterbatchcompositions. In addition, the optional metallocene processing aid alsoimproves the handleability of the masterbatch composition, as themasterbatch composition melts at lower temperatures that allow it to“wet out” or distribute more efficiently to provide betterprocessability and increased throughput.

The masterbatch compositions generally include a colorant, athermoplastic carrier, and optionally a metallocene processing aid andadditives, such as antioxidants, ultraviolet light absorbers, and lightstabilizers. In an embodiment, the metallocene polymer processing aid isan amorphous metallocene polypropylene copolymer obtained bypolymerizing a propylene monomer with about 2-15%, about 2-10%, or about5-10%, ethylene comonomer in the presence of a metallocene catalyst. Inan embodiment, the metallocene polymer processing aid exhibits a densityof about 0.87-0.93 g/cm3, a drop point of about 80-145° C., and aviscosity of about 60-6300 mPas. In an embodiment, the metallocenepolymer processing aid may have a range from amorphous to highlycrystalline.

In an embodiment, the processing aid is a metallocene polymer which is ageneral term for a polymer in which metallocene is used as a catalystfor polymerization. The metallocene polymer processing aid is not ametallocene resin as is used in conventional masterbatches and hasdifferent structural and physical properties therefrom. This metalloceneprocessing aid is a polymer having higher monodispersibility and anarrower molecular weight distribution (for instance, Mw/Mn<2 in thecase of metallocene polyethylene) than a polymer in which a conventionalZiegler catalyst, Ziegler-Natta catalyst or the like is used. It hasbeen found that the metallocene polymer processing aid allows a largeamount of colorant to be evenly dispersed in the presence of a highadditive concentration, giving the end product excellent coloration aswell as better physical and mechanical properties. Accordingly, thecomposition can provide molded or extruded articles having excellentmechanical strength.

Accordingly, the metallocene polymer is a preferred processing aidbecause it has a low drop point, low viscosity, low density, and goodwetting capability. The drop point of polymer ranges preferably from 80°C. to 120° C. The viscosity of the polymer is preferably 60 to 6300mPas. The density of the polymer is preferably 0.87 to 0.93 g/cm³. Themetallocene polymer may be present in the masterbatch composition up toabout 20%, preferably from about 4% to about 12%. Suitable metallocenepolymers include homopolymers of propylene or copolymers of propylenewith one or more olefins or grafted with other polymers. Copolymers ofpropylene with ethylene are preferred. The ethylene content of thecopolymers is from 0.1% to about 20%, preferably from about 2% to about10%.

The metallocene polymer processing aid is highly compatible with variouscarrier resins. Illustrative examples of thermoplastic carriers arehomopolymers or copolymers of high and low density polyethylene, highand low density polypropylene, polystyrene, polyoxymethylene,polyethylene terephthalate, polybutylene terephthalate, polymethylmethacrylate, polyether sulfones, polysulfones, polyether ketones,polystyrene copolymers, acrylonitrile-butadiene-styrene terpolymers,polyamides such as nylon-6 or nylon-6,6, polyvinyl chloride andcopolymers of ethylene with 0.1-20 mol % of 1-butene, 1-pentene,1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-undecene, otherimpact modified alloys, or mixtures thereof. The polymer to be and thecarrier polymer of the masterbatch can be, but do not have to be, thesame.

Colorants added to the masterbatch may comprise pigments, single pigmentdispersions, dyes, nano composites, coated micas, powdered aluminum andother metals, optical brighteners, fluorescents, phosphorescents, ormixtures thereof. Pigments may be at least one or a combination oforganic pigments and inorganic pigments, and there is no particularlimitation. When organic pigments are used, the organic pigments may bepresent up to about 50% by weight of the masterbatch composition. In apreferred embodiment, the organic pigments are present in a range fromabout 10 to about 40% by weight of the masterbatch composition. Ifinorganic pigments are used, the inorganic pigments may be present up toabout 75% by weight of the masterbatch composition. In a preferredembodiment, the inorganic pigments are present in a range from about 15%to about 75% by weight of the masterbatch composition. In anotherembodiment, both organic and inorganic pigments are used, and theorganic pigments may be present up to about 20% and the inorganicpigments may be present up to about 60%. In one embodiment, the organicpigment is present from about 3% to about 20% and the inorganic pigmentis present from about 10% to about 60%.

Illustrative examples of the organic pigments include azo and disazopigments such as azo and disazo lake, Hansas, benzimidazolones,diarylides, pyrazolones, yellows and reds; polycyclic pigments such asphthalocyanines, quinacridones, perylenes, perinones, dioxazines,anthraquinones, isoindolins, thioindigo, diaryl or quinophthalonepigment, Aniline Black, or mixtures thereof. Illustrative examples ofthe inorganic pigments include inorganic pigments such as titaniumoxide, titanium yellow, iron oxide, ultramarine blue, cobalt blue,chromic oxide green, Lead Yellow, cadmium yellow and cadmium red, carbonblack pigments, and mixtures thereof. The organic and inorganic pigmentscan be used singly or in combination. These pigments may be in any formof a dry powder, single pigment dispersions made conventionally oraccording to this process, or mixtures thereof.

In an embodiment, the colorant is about 15-80% by weight, thethermoplastic carrier is about 9-60% by weight, and the metallocenepolymer is about 2-20% by weight. In another embodiment, the colorant isselected from the group consisting of organic pigment, inorganicpigment, single pigment dispersion, dye, coated mica, powdered aluminum,optical brightener, fluorescent, and phosphorescent. In yet anotherembodiment, the colorant comprises an organic pigment about 5-50% byweight. In an embodiment, the colorant comprises an organic pigmentabout 10-40% by weight. In an embodiment, the colorant comprises aninorganic pigment about 0-80% by weight. In an embodiment, the colorantcomprises an organic pigment about 3-40% by weight and an inorganicpigment about 10-60% by weight.

Optionally, the masterbatch composition may also comprise an additive.Illustrative examples are ultraviolet light absorbers, lightstabilizers, antioxidants, flame-retardants, antibacterial agents,surface tension reducers, deodorizing agents, anti-static agents,anti-blocking agents, plasticizer agents, blowing agents, fillers, andother known additives, or mixtures thereof.

Ultraviolet light absorbers (UVA) shield the polymer from UV light byabsorbing light energy and releasing the absorbed light energyharmlessly as heat energy. Hindered amine light stabilizers (HALS)scavenge radical intermediates formed in the photo-oxidation process.The higher the concentration of UVA and/or HALS, the greater theprotection of the polymer (both the masterbatch carrier and the endproduct) from degradation and the color from fading. UVAs and HALS canbe added up to about 45% by weight of the masterbatch. Preferred UVAsand HALS include those of the TINUVIN® grades from BASF SE. Illustrativeexamples of UVA's and HALS include salicylic acid derivatives such asphenyl salicylate, p-t-butyl salicylate, etc., benzophenone system suchas 2,4-dihydroxy benzophenone, 2-hydroxy-4-methoxybenzophenone, etc.,benzotriazole system such as2-(2′-hydroxy-3′,5′-di-t-butylphenyl)benzotriazole,2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole, etc.,hindered amine system such as bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, dimethylsuccinate-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethyl piperidinecondensation product, 2-hydroxybenzophenones, e.g.2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,2-hydroxy-4-octoxybenzophenone, and 5,5′-methylenebis(2-hydroxy-4-methoxybenzophenone);2-(2′-hydroxyphenyl)benzotriazoles, e.g.2-(2′-hydroxy-5′-methylphenyl)benzotriazole,2-(2′-hydroxy-5′-t-octylphenyl)benzotriazole,-(2′-hydroxy-3′,5′-di-t-butylphenyl)benzotriazole,2-(2′-hydroxy-3′,5′-di-t-butylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′,5′-dicumylphenyl)benzotriazole, and 2,2′-methylenebis(4-t-octyl-6-benzotriazolyl)phenol; benzoates, e.g. phenylsalicylate,resorcinol monobenzoate,2,4-di-t-butylphenyl-3′,5′-di-t-butyl-4′-hydroxybenzoate, andhexadecyl-3,5-di-t-butyl-4-hydroxybenzoate; substituted oxanilides, e.g.2-ethyl-2′-ethoxyoxanilide and 2-ethoxy-4′-dodecyloxanilide;cyanoacrylates, e.g. ethyl-alpha-cyano-beta, beta-diphenylacrylate andmethyl-2-cyano-3-methyl-3-(p-methoxyphenyl)acrylate, and any other knownUVA, or mixtures thereof.

Additional illustrative examples of HALS include2,2,6,6-tetramethyl-4-piperidylstearate,1,2,2,6,6-pentamethyl-4-piperidylstearate,2,2,6,6-tetramethyl-4-piperidylbenzoate,bis(2,2,6,6-tetramethyl-4-piperidylsebacate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate,tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)-di(tridecyl)-1,2,3,4-butanetetracarboxylate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)-2-butyl-2-(3′,5′-di-t-butyl-4-hydr-oxybenzyl)malonate,1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol/diethyl succinatepolycondensate, 1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane/dibromoethane polycondensate,1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane/2,4-dichloro-6-t-octy-1amino-s-triazine polycondensate,1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane/2,4-dichloro-6-morpho-1ino-s-triazine polycondensate, and the like, or mixtures thereof.

Antioxidants, including processing stabilizers, can be added to themasterbatch composition up to about 15% by weight of the masterbatch.Peroxide polymer degradation generally occurs during processing (e.g.due to heat or shear), or at the time of light exposure. Peroxideradicals may be formed during this period, which in turn may lead to theformation of hyperoxides. Antioxidants are incorporated into polymers tostabilize peroxide radicals to prevent degradation. Optimal polymerstability is achieved when the initial molecular weight and/or theinitial color of the polymer is maintained. Therefore, the presentmasterbatch composition provides a higher degree of protection byachieving higher additive concentrations without sacrificing colorantconcentration. In one embodiment, both UVAs (and/or HALS) and anantioxidant may be added up to about 60% by weight of the masterbatch.It is preferred in such embodiments that the UVAs (and/or HALS) areadded up to about 45% by weight of the masterbatch, and the antioxidantis added up to about 15% by weight of the masterbatch. Stericallyhindered phenols or HALS are preferred antioxidants, particularlysterically hindered phenols of the Irganox® grades from BASF SE. Otherillustrative examples of antioxidants include a phenol system such as2,6-di-t-butyl-p-Cresol,pentaerythritol-tetrakis-(3,5-di-t-butyl-4-hydroxyphenyl) propionatemethyl phenol, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl) propionate,etc., phosphorus system such as tris(2,4-di-t-butylphenyl)phosphate,distearylpnetaerythritol diphophate,tetrakis(2,4-di-t-butylphenyl)-4,4′-biphenylene phosphonate, etc.,sulfur system such as distearyl-3,3′-thiodipropionate,pentaerythritol-tetrakis-(3-laurylthiopropionate), hindered phenol typeantioxidants and peroxide decomposers, HALS (as set described above), ormixtures thereof.

Illustrative examples of hindered phenol type antioxidants are2,6-di-t-butyl-4-methylphenol, styrenated phenol,n-octadecyl-3-(3,5-di-t-butyl-4-hydroxylphenyl) propionate,2,2′-methylene bis(4-methyl-6-t-butylphenol),2-t-butyl-6-(3-t-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenylacrylate,2-[1-(2-hydroxy-3,5-di-t-pentylphenyl)ethyl]-4,6-di-t-pentylphenylacrylate, 4,4′-butylidene bis(3-methyl-6-t-butylphenol),4,4′-thio-bis(3-methyl-6-t-butylphenol), alkylated bisphenol, tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)-proprionate] methane,3,9-bis[2-{3-(3-t-butyl-4-hydroxy-5-methylphenyl)-propionyloxy}-1,1-dimethylethyl]-2,4,8,10-tetraoxyspiro[5.5]undecane, or mixtures thereof.

Illustrative examples of peroxide decomposers are organic phosphorustype peroxide decomposers, such as trisnonylphenylphosphite,triphenylphosphite and tris(2,4-di-t-butylphenyl)phosphite; and organicthio type peroxide decomposers, such as dilauryl-3,3′-thiodipropionate,dimyristyl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate,pentaerythrityltetrakis(3-laurylthiopropionate),ditridecyl-3,3′-thiodipropionate and 2-mercaptobenzimidazole, ormixtures thereof.

Illustrative examples of flame-retardants are phosphoric acid systemssuch as allyl diallyl phosphate, cresyl diphenyl phosphate, octyldiphenyl phosphate, triallyl phosphate, tributyl phosphate, triphenylphosphate, tris(.beta.-chloroethyl)phosphate,tris(dichloropropyl)phosphate, tris(2,3-dibrompropyl)phosphate,tris(bromo-chloropropyl)phosphate, etc., chlorine system such aschlorinated paraffin, chlorinated polyphenyl, perchloropentacyclodecane,etc., bromine system such as tetrabromoethane, tetrabromobutane,hexaborombenzene, decabromodiphenyloxide, polydibrornophenyloxide,bis(tribromophenoxy)ethane, ethylene bisbromonorbornane dicarboxylmide,ethylene bistetrabromophthalimide, etc. reaction type such as chlorendicacid anhydride, tetrabromo phthalic anhydride, tetrabromo bisphenol A,dietoxy-bis-(2-hydroxyethyl)-aminomethyl phosphate, dibormcresylalycidyl ether, etc., or mixtures thereof.

Illustrative examples of antibacterial agents include, phenol etherbased antibacterial agents, such as those having the phenol group in theintramolecular skeleton, for example, 10,10′-oxybisphenoxa arsine, etc.;natural antibacterial agents, such as those having tropolone as acentral skeleton, for example, hinokitiol, beta-dolabulin, etc., asglycerol ester of fatty acid, lower fatty acid monoglycerol ester,sucrose fatty acid ester, polyglycerol fatty acid ester, for example,monoglyceride caprylate, monoglyceride caprate, lauric acidmonoglyceride, Sugar-ester palpitate, decaglycerol monocaprate,hexaglycerol caprylate, etc., zeolite-based compounds, part or whole ofion-exchangeable ion in zeolite-based compounds, for example, part orwhole of sodium ion, calcium ion, potassium ion, magnesium ion, ironion, etc. is substituted with ions with antibacterial property, such assilver ion, copper ion, zinc ion, ammonium ion, etc. can be exemplified.These compounds can be used singly or two or more kinds of them can beused in combination.

Fillers are typically inexpensive particulate materials that do notcontribute to the color. Illustrative examples of fillers include, amongothers, talcs, micas, clays, nano-clays, silicas, or mixtures thereof.

The masterbatch composition described herein may contain other additivesor ingredients and should not be limited to the stated formulations. Inone embodiment, a dispersion package can be added to the masterbatchcomposition in an amount up to about 25% by weight of the masterbatch.In another embodiment, the dispersion package is added in an amount fromabout 2% to about 8% based on the weight of the masterbatch. Thedispersion package can be waxes, metal salts, surfactants, couplingagents, organometallic compounds, and mixtures thereof. Illustrativeexamples include conventional polyethylene and polypropylene waxes andderivatives thereof such as acid-modified products and metal salts ofacid-modified products, as well as zinc stearate, magnesium stearate,aluminum stearate, calcium stearate and ethylene bisteramide, andmixtures thereof.

Before actual mixing of the masterbatch, the components for each of themain feed and the secondary feed can be premixed if desired, for whichdrum or tumbler mixers may be used. In the actual dry blend mixingprocess, the mixing can be performed in a blade-type mixer. In oneembodiment, the colorant blend is mixed in a high intensity mixer alongwith some wax until the wax melts and encapsulates the colorants,resulting in a well dispersed, densified colorant blend. Additionaldispersion takes place in an extruder, for example a single-screw ortwin-screw extruder, however, any suitable equipment known in the artmay be used. Illustrative examples include Buss kneaders, planetary rollextruders, open double-trough kneaders, rapid stirrers, internal fluxingmixers such as Banbury mixers and Farrel continuous mixers, or the like.

In a main or primary feed the following are processed in a dryblend/extrusion configuration: a colorant, and optionally an additive, acarrier resin, and a polymer processing aid. In one embodiment, thecarrier resin in the primary feed may be present up to about 10% of thetotal formulation weight and can be blended in with the pigments andadditives in the primary feed in a dry blend stage to assist with thepigment wetting out process. Alternatively, no carrier resin can beadded to the primary feed.

The primary feed is in connection with a secondary feed at the primaryfeed port, upstream the primary feed port, downstream the primary feedport, or a combination thereof. As illustrated in FIG. 1, a process flowdiagram is shown wherein the primary feed is upstream the secondaryfeed, in FIG. 2, the secondary feed is illustrated upstream the primaryfeed, and in FIG. 3, the primary feed and secondary feed are connectedat the same feed port. The feed port, as illustrated in the Figures, mayrepresent a meter, a valve, an opening, and any combination thereof. Theconveying zone illustrates the conveyance of the materials to themelting, dispersing, and metering zones, which may include, but notlimited to kneading, compressing, reversing elements, etc.

In an embodiment, the secondary feed includes a majority of the carrierresin in a molten state. All or most of the carrier resin can beintroduced to the masterbatch through the secondary feed. In alternativeembodiments, the secondary feed is introduced in a molten state via asecondary feed port about 8 L/D upstream or downstream. The secondaryfeed may be produced by a relatively small secondary extruder, such as alow L/D single screw extruder, or a melt pump. In one embodiment, thesecondary feed can be introduced by side feeding. In an embodiment,pre-melted resin carrier in the secondary feed stream has an increasedmelt flow compared to the low melt/high processed powder from theprimary feed stream.

Introduction of the carrier resin from the secondary feed as a meltstream results in a higher density composition as compared to the bulkdensity of the pellets, flakes, or powder. Combination of themain/primary and secondary feeds allow for a higher volume of colorantsand additives to be introduced via the primary feed. The secondary feedcontaining the molten carrier resin begins to wet out the pigmentimmediately upon contact with the mixture from the main stream.

Use of a secondary feed provides benefits from maintenance and cleaningperspectives, as the corresponding secondary extruder or melt pumprequires a changeover only when the resin is altered or changed, suchthat merely a simple purge with the next resin is needed. Based on this,the addition of a carrier stream in the secondary feed saves time andmoney with regard to maintenance and cleaning of at least the secondaryfeed extruder/melt pump.

An additional benefit of using a secondary feed includes havingadditional room for active ingredients to be processed in the extruderand wetted out with molten polymer, which takes up less free volume inthe extruder than the pellet form. This allows for processing anincreased loading of low bulk density ingredients.

Furthermore, use of a secondary feed, whether it is concurrent,upstream, or downstream the primary feed, will increase the efficiencyof the work that the extruder can provide by filling flights with lowbulk density ingredients with low temperature melting metallocenepolymer and dispersing aids that will wet our early and add density tothe powder ingredients, so that once the molten resin is introduced inits most dense state, the flights of the extruder are full of amasterbatch, as opposed to being partially full (e.g. ¼ or ½), such asthose of conventional masterbatch extrusion processes. Filling flightsallows for an increase of work and pressure within the extruder, whichfacilitates dispersion and high throughput rates. Correspondingly,another advantage of utility of a secondary feed is that the length ofthe extrusion time can be shortened because the resin does not need tobe melted and there is increased efficiency of utilizing full flights.Use of a secondary feed allows for many benefits without sacrificingproduction rates.

In an embodiment, the secondary feed is processed as a continuousprocess operated via a single screw or continuous mixer. In anotherembodiment, the secondary feed is processed in a batch process.

Furthermore, the secondary feed may be processed by use of a gentlescrew configuration with minimal mixing, yet maintain a masterbatchcomposition with high loadings. In an embodiment, the secondary feed ispaired with a gentle screw configuration, a dispersive screw with mostlykneaders, a single screw extruder, or a twin-screw extruder.

In another embodiment, a primary feed and a secondary feed may beintroduced at a first feed throat and yet maintain a masterbatchformulation with at least 50% inorganic pigment loading.

In exemplary embodiments, as shown below in Tables 1-7, a set of trialsfor masterbatch compositions are formulated from the split streamprocess described. Tables 1-4 provide for formulations for Red (RedFormulation for Polyolefins), Green (Green Formulation for Polyolefins),Purple (Purple Pearl Formulation for Polyolefins), and Yellow (YellowFormulation for Polyolefins) pigmented masterbatch compositions that arecompared to a conventional compositions developed from a dryblend/extrusion process as shown below where the components of the colorfeed stream are dry blended and then introduced upstream of the moltenresin feed stream. Tables 5-7 provide exemplary formulations forpolystyrene and polyamide in different colors and at a variety ofprimary to secondary weight ratios. As seen in Table 5, theseformulations effectively double the dye loading in comparison toconventional approaches.

As referred to herein, the G2® Formula is developed according to U.S.Pat. No. 7,442,742, wherein G2 is a registered trademark owned byCarolina Color Corporation located in Salisbury, N.C.

TABLE 1 Red Formulation for Polyolefins G2 Formula 60:40 Split 65:35Split 70:30 Split 75:25 Split Component % of Total % of Total % of Total% of Total % of Total Pigment Red 122 11.86 13.47 14.59 15.72 16.84Pigment Red 101 4.14 4.70 5.09 5.49 5.87 Pigment Red 170 12.65 14.3715.57 16.77 17.96 Polymer Processing Aid 5.00 4.73 5.13 5.52 5.91Dispersion Aid 3.00 3.78 4.10 4.42 4.73 PE Flake 20.00 18.92 20.50 22.0823.65 PE Pellets 43.33 40.00 35.00 30.00 25.00 Pigment Loading v.Standard 100% 114% 123% 132% 142%

Table 1 illustrates the pigment loading for a Red Formulation forPolyolefins of various masterbatch compositions formed from a splitstream, wherein the ratio of the primary feed to the secondary feed is60:40, 65:35, 70:30, or 75:25 by weight. As the ratio of the primaryfeed to secondary feed increases, the loading of pigment also increases.As shown in Table 1, a 75:25 split results in a higher bulk density ofred pigment of approximately 42% higher loading than the G2 Formula.

TABLE 2 Green Formulation for Polyolefins G2 60:40 65:35 70:30 75:2580:20 Formula Split Split Split Split Split % of % of % of % of % of %of Component Total Total Total Total Total Total Pigment Yellow 194 5.095.65 6.13 6.60 7.07 7.54 Pigment Green 17 16.30 18.11 19.61 21.12 22.6324.14 Pigment Green 7 18.28 20.30 22.00 23.69 25.38 27.07 Pigment Black7 0.35 0.39 0.42 0.46 0.49 0.52 Dispersion Aid 4.00 4.44 4.81 5.18 5.555.92 Polymer Processing Aid 7.00 6.48 7.02 7.56 8.10 8.64 PE Flake 5.004.63 5.01 5.40 5.78 6.17 PE Pellets 43.97 40.00 35.00 30.00 25.00 20.00Pigment Loading v. 100% 111% 120% 130% 139% 148% Standard

Table 2 illustrates the pigment loading for a Green Formulation forPolyolefins of various masterbatch compositions formed from a splitstream, wherein the ratio of the primary feed to the secondary feed is60:40, 65:35, 70:30, 75:25, or 80:20 by weight. Similar to the abovedescribed Table 1, as the ratio of the primary feed to secondary feedincreases, the loading of pigment also increases. As shown in Table 2,an 80:20 split results in a higher bulk density of green pigment ofapproximately 48% higher loading than the G2 Formula.

In exemplary embodiments, as shown below in Tables 3 and 4, a set oftrials for Purple (Purple Pearl Formulation for Polyolefins) and Yellow(Yellow Formulation for Polyolefins) pigmented masterbatch compositionsare formulated from the split stream process described herein andcompared to a conventional masterbatch formulated developed from a dryblend/extrusion process:

TABLE 3 Purple Pearl Formulation for Polyolefins G2 Formula 65:35 Split80:20 Split Component % of Total % of Total % of Total Violet SatinPearl 5.90 6.85 8.44 Violet Sparkle Pearl 5.90 6.85 8.44 Red Satin Pearl4.72 5.49 6.75 Pigment Blue 29 9.44 10.97 13.51 Pigment Red 122 1.131.32 1.62 Polymer Processing Aid 4.00 4.64 5.72 Dispersion Aid 4.50 4.995.79 Mineral Oil 2.00 2.32 2.86 Slip Agent 13.34 15.49 19.07 PP Flake5.00 5.81 7.15 PP Pellets 44.06 35.00 20.00 Pigment Loading v. Standard100% 112% 142%

Table 3 illustrates the pigment loading for a Purple Pearl Formulationfor Polyolefins of various masterbatch compositions formed from a splitstream, wherein the ratio of the primary feed to the secondary feed is65:35 or 80:20 by weight. Similar to the above described Tables 1 and 2,as the ratio of the primary feed to secondary feed increases, theloading of pigment also increases. As shown in Table 3, an 80:20 splitresults in a higher bulk density of purple pigment of approximately 42%higher loading than the G2 Formula.

The blend containing an 80:20 split includes approximately 58% activeingredients (e.g. pigments and slip agent), including approximately 19%slip agent. Due to the reduced L/D for the primary extruder there is abrighter appearance and less reduction of particle size for the PurplePearl compared to the G2 Formula as run on a conventional masterbatchingtwin screw.

TABLE 4 Yellow Formulation for Acrylonitrile Butadiene Styrene (ABS) G2Formula 60:40 Split 70:30 Split Component % of Total % of Total % ofTotal Pigment White 6 0.55 1.18 1.38 Pigment Yellow 109 5.51 11.77 13.73Pigment 110 5.51 11.77 13.73 Solvent Yellow 33 4.41 9.41 10.99Dispersion Aid 2.10 4.48 5.23 SAN Powder 10.00 21.38 24.94 ABS Pellets71.93 40.00 30.00 Pigment Loading v. Standard 100% 212% 248%

Table 4 illustrates the pigment loading for a Yellow Formulation forPolyolefins of various masterbatch compositions formed from a splitstream, wherein the ratio of the primary feed to the secondary feed is60:40 or 70:30 by weight. Similar to the above described Tables 1, 2,and 3, as the ratio of the primary feed to secondary feed increases, theloading of pigment also increases. As shown in Table 4, a 70:30 splitresults in a higher bulk density of yellow pigment of approximately 48%higher loading than the G2 Formula. The blend containing a 70:30 splitincludes over approximately 27% hard to disperse organic pigments, inaddition to approximately 11% dye.

Each of the ratios described in Tables 3 and 4 have been verified by ashtests and by molding plaques.

TABLE 5 Red Dye Formulations for Polystyrene Conventional 46:54 Split,Component Formulation, wt. % wt % of total Solvent Red 24 10.39 20.77Solvent Red 23 3.05 6.10 Solvent Red 26 1.98 3.96 Polystyrene Powder30.00 15.00 Impact Polystyrene Pellets 53.28 54.17 Dye Loading v.Traditional 100% 200%

Table 5 compares formulations for a conventional, prior art systemagainst a formulation according to the inventive split stream process.In this particular case, a red dye formulation was desired, with theprimary feed to secondary feed weight ratio set at 46:54, whichrepresents one of the lower ends of the inventive range. Nevertheless,the resulting formulation still has double the dye loading as comparedto conventional formulations. As such, this serves as one example of thewell-dispersed, highly loaded masterbatch compositions attainableaccording to certain aspects of the invention disclosed herein.

TABLE 6 Pigment and Dye Formulations for Polystyrene Blue Formulation,Yellow Formulation, Component 87:13 Split, wt. % 86:14 Split, wt. %Pigment White 6 57.27 25.48 Solvent Blue 101 13.22 — Solvent Violet 130.88 — Pigment Yellow 24 — 31.72 Solvent Yellow 72 — 6.51 Pigment Black7 — 0.02 Dispersant 1.00 2.00 Powdered Polystyrene 14.63 20.27 ImpactPolystyrene Pellets 13.00 14.00

Table 6 describes blue and yellow colored formulations based uponpolystyrene-based thermoplastic carriers. Notably, in both formulations,colorants comprise well over 60 wt. % of the total formulation, whereasthe thermoplastics account for about one third or less. Thus, theseformulations exemplify high ratio (primary:secondary) split streamprocesses which also result in well-dispersed, highly loaded masterbatchcompositions.

TABLE 7 Yellow Pigment and Dye Formulation for Polyamide (PA) 86:14Split Component % of Total Pigment White 6 41.12 Solvent Yellow 33 17.62Solvent Orange 60 0.38 Anti-oxidant 0.15 Pigment Dispersant 1.00 PAPowder 25.73 PA Pellets 14.00

Table 7 shows a high ratio yellow pigment and dye-based formulationincorporating polyamide as the thermoplastic carrier.

Notably, Tables 5-7 illustrate the range of weight percentages forcolorants that can be attained according to certain aspects of theinvention. As the primary to secondary ratio is increased (i.e., moreprimary feed is provided relative to the secondary feed, by weight),even higher levels of loading may be attained, particularly for thepolystyrene-based formulations. In some embodiments, this ratio mayinclude 90:10 and even 95:5 splits. Conversely, by definition of a splitstream process, necessarily requires a secondary feed.

Masterbatch, as used therein, is a term of art wherein a colorant(and/or other additives) is dispersed within a thermoplastic carrier. Inturn, these masterbatch compositions may be mixed into subsequentmanufacturing processes to impart colorants and other additives tomaterials made according to these processes. As such, the more highlyloaded a masterbatch can be, the more effectively and efficiently it canbe employed to its desired effect. The masterbatches according tocertain aspects of the invention herein may be loaded, on a weight basisaccording to the disclosure above.

The masterbatch may be introduced to any compatible polymer andprocessed. It is understood that the masterbatch composition of thepresent disclosure can be used for coloring polymers formed into variousshapes, such as sheet, film, tube, bottles, containers, molded productsand other molded articles. The term processing is used herein todescribe the conversion of polymers into articles of a desired shape.Illustrative examples of processing are extrusion molding, injectionmolding, blow molding, compression molding and calendering. The additionof the masterbatch to the melt-processible polymer can be accomplishedby any means known in the art. It is possible to use the same methods asfor preparing the masterbatch itself. It is understood that themasterbatch carrier polymer can be the same or different than themelt-processible polymer. The masterbatch composition may be introducedand processed via a batch or continuous process. In one illustrativeembodiment, the masterbatch may be introduced to the melt-processiblepolymer and processed on a rubber compounding mill, simple kneader, orin a Banbury or other internal mixer or in a mixing extruder.Alternatively, the masterbatch can be metered to the feed section of anextruder by appropriate devices. Continuous processes can be carriedout, for example, in rapid mixers, single-screw extruders, twin-screwextruders, Buss kneaders, planetary roll extruders, open double-troughkneaders or rapid stirrers. Continuous processes are preferred.

Although the embodiments of the present teachings have been described inthe accompanying embodiments and in the foregoing detailed description,it is to be understood that the present teachings are not to be limitedto just the embodiments disclosed, but that the teachings describedherein are capable of numerous rearrangements, modifications andsubstitutions.

What is claimed is:
 1. A process for making a masterbatch compositioncomprising: providing an additive mixture including a colorant and anoptional additive component or components to a primary feed; melting athermoplastic and providing the melted thermoplastic to a secondary feedthat is physically separated from the primary feed; combining thesecondary feed with the primary feed and extruding the resultant mixtureto form a masterbatch composition having greater than 45 wt. % of theadditive mixture; and wherein, upon combining the primary and secondaryfeeds, a weight ratio of primary to secondary feed is greater than60:40.
 2. The process according to claim 1 wherein the weight ratio isless than 95:5.
 3. The process according to claim 1 wherein the weightratio is less than 90:10.
 4. The process according to claim 1 whereinthe additive component or components are present and include at leastone item selected from: a metallocene polymer, a polymer processing aid,a dispersion aid, a slip agent, mineral oil, and any combination of twoor more items herein.
 5. The process according to claim 1 wherein themasterbatch composition has up to 80 wt. % of colorant.
 6. The processaccording to claim 1 wherein the masterbatch composition has up to 50wt. % of organic pigment(s).
 7. The process according to claim 6 whereinthe organic pigment(s) is at least one item selected from: azo anddisazo pigments such as azo and disazo lake, Hansas, benzimidazolones,diarylides, pyrazolones, yellows and reds; polycyclic pigments,phthalocyanines, quinacridones, perylenes, perinones, dioxazines,anthraquinones, isoindolins, thioindigo, diaryl and/or quinophthalonepigment, Aniline Black, and any combination of two or more items herein.8. The process according to claim 1 wherein the masterbatch compositionhas up to 75 wt. % of inorganic pigment(s).
 9. The process according toclaim 8 wherein the inorganic pigment(s) is at least one item selectedfrom: titanium oxide, titanium yellow, iron oxide, ultramarine blue,cobalt blue, chromic oxide green, Lead Yellow, cadmium yellow andcadmium red, carbon black pigments, and any combination of two or moreitems herein.
 10. The process according to claim 1 wherein the masterbatch composition includes organic and inorganic pigments.
 11. Theprocess according to claim 1 wherein the masterbatch composition hasbetween 9 to 55 wt. % of thermoplastic.
 12. The process according toclaim 1 wherein the masterbatch composition has up to 60 wt. % of theadditive component(s).
 13. The process according to claim 1 wherein theadditive component or components are present and include at least oneitem selected from: an antioxidant, a light stabilizer, an ultravioletlight absorber, and any combination two or more items herein.
 14. Theprocess according to claim 1 wherein the additive component orcomponents are present and consist essentially of at least one itemselected from: antioxidants, ultraviolet light absorbers, lightstabilizers, flame-retardants, antibacterial agents, surface tensionreducers, deodorizing agents, anti-static agents, anti-blocking agents,plasticizer agents, fillers, blowing agents, and any combination of twoor more items herein.
 15. The process according to claim 1 whereinconstituents of the secondary feed are mixed via a dry blending processprior to melting the thermoplastic.
 16. A process for making amasterbatch composition from a split stream process comprising: a)mixing a colorant into a mixture in a primary feed; b) pre-melting athermoplastic carrier in a secondary feed; c) combining the mixture ofthe primary feed and the secondary feed, including the meltedthermoplastic carrier, at a ratio (by weight) of primary feed tosecondary feed between 46:54 and 87:13; and d) extruding the combinedmixture to form a masterbatch composition having between 15 to 80 wt. %of colorant.
 17. The process according to claim 16 further comprising,prior to combining the mixture of the primary feed and the secondaryfeed, providing an additive in the primary feed and/or in the secondaryfeed so that the masterbatch composition has between 5 to 60 wt. % ofadditive.
 18. The process according to claim 17 wherein the additive isat least one item selected from: antioxidants, ultraviolet lightabsorbers, light stabilizers, flame-retardants, antibacterial agents,surface tension reducers, deodorizing agents, anti-static agents,anti-blocking agents, plasticizer agents, fillers, blowing agents, andany combination of two or more items herein.
 19. The process accordingto claim 18 wherein the masterbatch composition has between 9 to 60 wt.% of thermoplastic carrier.
 20. The process according to claim 19wherein the melted thermoplastic carrier consists essentially of atleast one item selected from: homopolymers and copolymers ofpolyethylene, polypropylene, polystyrene, polyoxymethylene, polyethyleneterephthalate, polybutylene terephthalate, polymethyl methacrylate,polyether sulfones, polysulfones, polyether ketones, polystyrenecopolymers, acrylonitrile-butadiene-styrene terpolymers, polyamides,polycarbonate, and any combination of two or more items herein.